As A Naturalistic Experience
(weikipedia)
As a naturalistic experience Other commentators see near death experiences as a purely naturalistic phenomenon. For example; a Swiss study (Blanke. et.al, 2002), published in Nature Magazine [4], found that electrical stimulation on the brain region known as the right angular gyrus repeatedly caused out-of-body experiences to the patient[5]. According to this perspective the etiology of the NDE is understood as a result of neurobiological mechanisms, related to such factors as epilepsy and brain stimulation. The similarities amongst the experiences of the many documented cases of NDE may be understood to signify that the pathology of the brain during the dying and reviving process is more or less the same in all humans, as suggested by Russian specialist Dr. Vladimir Negovsky in his book Clinical Death As Seen by Reanimator (Pravda, 2004). However, this model fails to explain NDEs that result from close brushes to death where the brain does not actually suffer trauma, such as a near-miss automobile accident.A well-known scientific hypothesis that attempts to explain NDEs was originally suggested by Dr. Karl Jansen (1995;1997) and deals with accounts of the side-effects of the drug Ketamine. Ketamine was used as an anesthetic on U.S. soldiers during the Vietnam War; but its use was abandoned and never spread to civilian use because the soldiers complained about sensations of floating above their body and seeing bright lights. Further experiments by numerous researchers verified that intravenous injections of ketamine could reproduce all of the commonly cited features of an NDE; including a sense that the experience is "real" and that one is actually dead, separation from the body, visions of loved ones, and transcendent mystical experiences.Ketamine acts in part by blocking the NMDA receptor for the neurotransmitter glutamate. Glutamate is released in abundance when brain cells die, and if it weren't blocked, the glutamate overload would cause other brain cells to die as well. In the presence of excess glutamate, the brain releases its own NMDA receptor blocker to defend itself; and it is these blockers Dr. Jansen (amongst others) hypothesize as the cause of many NDEs. Shawn Thomas, director of Neurotransmitter.net, has suggested that agmatine is the key substance involved in near-death experiences[6].Critics of Jansen's hypothesis point out that although some aspects of the experience may be similar, not all NDEs exactly fit the ketamine experience; and that while it might be possible to chemically simulate the experience, this does not refute the possibility that spontaneous NDEs have a spiritual component. As Dr. Jansen himself notes:Claims that NDE's must have a single explanation (e.g. Ring, 1980), or that a scientific theory must explain all of the experiences ever given the name of NDE (e.g. Gabbard and Twemlow, 1989) are difficult to justify (Jansen, 1995). Indeed Dr. Jansen's own shifting perspective on the conclusions to be drawn from the ketamine-NDE analogy has been notable. He started out as an unequivocal debunker of the notion that NDE's are evidence of a spiritual (or at least transnormal) realm. But with time he has developed a more agnostic hypothesis: that ketamine may in fact be one particularly powerful trigger of authentic spiritual experiences - of which near-death may be another. In each case, according to Jansen's more recent pronouncements, all we can say is that the subject gets catapulted out of ordinary 'egoic' consciousness into an altered state - we cannot comfortably rule out the possibility that the 'worlds' disclosed in these 'trips' have ontological status. Latterly, therefore, Jansens position appears closer to thinkers like Daniel Pinchbeck (2002), who has written a book on hallucinogenic shamanism, and other names like Carl Jung, Ken Wilber and Stanislav Grof, than to thinkers like Susan Blackmore or Nicholas Humphrey (two particularly high-profile materialist skeptics).
Resumos Relacionados
- Ketamine Brain Damage And The Near Death Experience
- As An Afterlife Experience
- Evidence Of Life After Death
- Near-death Research
- Understanding Consciousness.
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